The present invention relates generally to dump bodies for off-highway rubber tired haulage vehicles, such as dump trucks. More specifically, the present invention relates to a joint isolation system for reducing stress in joints between adjacent plates or other components in a dump body.
Dump bodies for off-highway rubber tired haulage vehicles are typically constructed from a plurality of plates that have been welded together. According to common practice, dump bodies include a floor, sidewalls, and a front wall. Many times a cab protector is attached to the top edge of the front wall in order to protect the truck cab during loading operations.
According to common practice, the plates which form the bulk of the load carrying surfaces are joined, such as by welding, to adjacent plates and/or supporting frame members to form the finished dump body. In order to keep the overall weight of the dump body below a desired level, manufacturers often try to use the thinnest plates possible. However, it is known that thin, flat plates are generally not well suited for carrying loads perpendicular to their surface.
Although flat plates can be stiffened somewhat by increasing the thickness of the plates, in dump body applications merely thickening all of the plates is not a desirable option, as such an approach increases the weight of the dump body, thus lowering the hauling capacity of the haulage vehicle. Consequently, thin plates are often welded to other reinforcing supporting plates disposed at intervals, or are otherwise connected to and supported by a network of supporting frame members. The thin plates serve the goal of keeping the overall weight down, while the other reinforcing members provide the necessary strength. Two examples of typical prior art construction techniques are shown in FIGS. 8 and 9, both of which experience significant stress along the weld lines indicated as W1 and W2 in FIG. 8, and W3 in FIG. 9.
Unfortunately, according to conventional construction techniques, such joints often experience problems, such as, by way of example rather than limitation, problems with metal fatigue. This metal fatigue is often most prevalent precisely at the weld lines in the dump body.